Growth of human T-cell lineage acute leukemia in severe combined immunodeficiency (SCID) mice and non-obese diabetic SCID mice

Primary leukemic cells from patients with acute lymphoblastic leukemia (ALL) can be injected intravenously into mice with severe combined immunodeficiency (SCID) to create a model of human leukemia. Leukemic cells disseminate to murine tissues in a clinicopathologic pattern similar to that seen in humans. Thus far, reports of engraftment of lymphoid leukemia in SCID mice have mainly been from patients with B-cell lineage ALL, for which engraftment occurs more frequently with cells from high-risk patients. There are few data on the engraftment of T-cell lineage ALL in SCID mice. Leukemic cells from 19 patients (16 adult and three pediatric) with T-cell lineage ALL were injected into SCID mice, with overt engraftment of 12 cases (63%). Engraftment of leukemia in SCID mice was associated with earlier death due to leukemia of the patient donors (P < .01, log-rank test). The recently developed non-obese diabetic (NOD)/SCID mouse may expand the uses of the SCID model. Cells from the seven patients with T-cell lineage ALL that failed to cause leukemia in SCID mice were injected into NOD/SCID mice. Overt leukemia engraftment was observed in all seven cases. Thus, growth of human T-cell lineage ALL cells in SCID mice was associated with a high-risk patient group. However, this association was not observed when NOD/SCID mice were used, suggesting that this model would no longer predict patients likely to die early of leukemia, but may provide a more realistic system for studying the biology and treatment of the disease.     

Isolation and propagation of human papillomavirus type 16 in human xenografts implanted in the severe combined immunodeficiency mouse

We report the isolation and propagation of human papillomavirus type 16, the main agent of cervical cancer, using human foreskin fragments implanted in severe combined immunodeficiency mice. The infection produced viral particles, and with each passage of the virus it caused lesions identical to intraepithelial neoplasia, the precursor to carcinoma.     

Establishment of a retinoic acid-resistant human acute promyelocytic leukaemia (APL) model in human granulocyte-macrophage colony-stimulating factor (hGM-CSF) transgenic severe combined immunodeficiency (SCID) mice

To understand the mechanisms and identify novel approaches to overcoming retinoic acid (RA) resistance in acute promyelocytic leukaemia (APL), we established the first human RA-resistant APL model in severe combined immunodeficiency (SCID) mice. UF-1 cells, an RA-resistant APL cell line established in our laboratory, were transplanted into human granulocyte-macrophage colony-stimulating factor (GM-CSF)-producing SCID (hGMTg SCID) mice and inoculated cells formed subcutaneous tumours in all hGMTg SCID mice, but not in the non-transgenic control SCID mice. Single-cell suspensions (UF-1/GMTg SCID cells) were similar in morphological, immunological, cytogenetic and molecular genetic features to parental UF-1 cells. All-trans RA did not change the morphological features of cells or their expression of CD11b. RA did not alter the growth curve of cells as determined by MTT assay, suggesting that UF-1/GMTg SCID cells are resistant to RA. These results demonstrate that this is the first RA-resistant APL animal model that may be useful for investigating the biology of this myeloid leukaemia in vivo, as well as for evaluating novel therapeutic approaches including patients with RA-resistant APL.     

Defective expression of early activation genes in cartilage-hair hypoplasia (CHH) with severe combined immunodeficiency (SCID)

PURPOSE OF STUDY: To examine factors which may predispose to tooth fracture, and to assess the compressive strengths of foods and sweets which are associated with tooth fracture in vivo. POPULATION STUDIED: Consecutive dental patients presenting with one or more fractured posterior teeth at the surgeries of three general dental practitioners, over a four-month period. METHOD: A pro forma was designed to elicit information on the factors associated with tooth fracture and the nature and extent of such fractures. Three general dental practitioners were requested to complete a pro forma for each patient presenting with a fractured posterior tooth over a four-month period. Foods and sweets considered to be associated with tooth fracture were identified and their compressive strengths tested. FINDINGS: A total of 129 cases of fractured posterior teeth were recorded, of which 48% occurred in the mandibular arch and 52% in the maxillary arch. In the mandible, 75% of tooth fractures occurred in molars while in the maxillary arch 50% occurred in molars. In 57% of cases assessed, no identifiable causative item was noted. Forty-five per cent of fractures were in teeth which had been restored on three or more surfaces. Compressive forces of 0.16KN to 2.2KN were obtained for food items implicated in tooth fractures. CONCLUSION: As mesio-occlusodistal restorations were identified as a major predisposing factor to tooth fracture in this study, with mandibular first molar teeth particularly affected, placement of cuspal coverage restorations may be considered to be a justifiable preventative measure in teeth identified as being at risk.     

Nonobese diabetic/severe combined immunodeficiency (NOD/SCID) mouse as a model system to study the engraftment and mobilization of human peripheral blood stem cells

Mobilized CD34(+) cells from human peripheral blood (PB) are increasingly used for hematopoietic stem-cell transplantation. However, the mechanisms involved in the mobilization of human hematopoietic stem and progenitor cells are largely unknown. To study the mobilization of human progenitor cells in an experimental animal model in response to different treatment regimens, we injected intravenously a total of 92 immunodeficient nonobese diabetic/severe combined immunodeficiency (NOD/SCID) mice with various numbers of granulocyte colony-stimulating factor (G-CSF) -mobilized CD34(+) PB cells (ranging from 2 to 50 x 10(6) cells per animal). Engraftment of human cells was detectable for up to 6.5 months after transplantation and, depending on the number of cells injected, reached as high as 96% in the bone marrow (BM), displaying an organ-specific maturation pattern of T- and B-lymphoid and myeloid cells. Among the different mobilization regimens tested, human clonogenic cells could be mobilized from the BM into the PB (P = .019) with a high or low dose of human G-CSF, alone or in combination with human stem-cell factor (SCF), with an average increase of 4.6-fold over control. Therefore, xenotransplantation of human cells in NOD/SCID mice will provide a basis to further study the mechanisms of mobilization and the biology of the mobilized primitive human hematopoietic cell.     

Bryostatin 1 affects P-glycoprotein phosphorylation but not function in multidrug-resistant human breast cancer cells

The function of P-glycoprotein (Pgp), which confers multidrug resistance by active efflux of drug, is thought to be dependent on phosphorylation. Previous studies have suggested that protein kinase C (PKC) plays an important role in Pgp phosphorylation. We report here the effects of bryostatin 1, a unique PKC activator and inhibitor, on Pgp function in a multidrug-resistant MCF-7 human breast cancer subline which overexpresses PKC-alpha. Bryostatin 1 (100 nM) decreased Pgp phosphorylation after 24 h of treatment. In contrast, it did not affect Pgp function as demonstrated by the accumulation of [3H]vinblastine and rhodamine 123. We compared the effect of bryostatin 1 treatment on PKC-alpha with that of the phorbol ester 12-O-tetradecanoylphorbol-13-acetate (200 nM). 12-O-tetradecanoylphorbol-13-acetate caused translocation of PKC-alpha from the cytosol to the cell membrane after a 10-min treatment and its down-regulation after 24 h of treatment. Likewise, bryostatin 1 (100 nM) caused translocation, but only after longer treatment (1 h), and it caused down-regulation of PKC-alpha at 24 h of treatment. Thus, while the MCF-7TH cells overexpress the PKC-alpha isoform, and its down-regulation by bryostatin 1 is associated with decreased Pgp phosphorylation, these alterations do not modulate drug transport. We conclude that, while bryostatin 1 may be useful clinically because of its ability to inhibit PKC, it is not able to reverse Pgp-mediated multidrug resistance.     

Human recombinant interleukin-4 (HurIL-4) improves SCID mouse reconstitution with human peripheral blood lymphocytes

The application of human-scid mouse chimera (hu-scid) technology has some limitations, because of the variable amounts and functional heterogeneity of human cells recovered from engrafted mice. Attempts to optimize the construction of hu-scid chimeras with human peripheral blood mononuclear cells (Hu-PBMC) by using in vivo anti-asialo GM1 antibody treatment in mice in order to eliminate natural killer cells have been published by other authors with interesting results. In this study, Hu-PBMC were incubated in vitro with human recombinant interleukin-4 (HurIL-4) or human recombinant interleukin-2 (HurIL-2) for two hours and were intraperitoneally transferred into scid mice. Total human IgM and IgG levels in hu-scid sera, human cell markers in the thymus and in the spleen of grafted mice were considered as parameters of successful engraftment. HurIL-4 significantly enhanced human immunoglobulin production while HurIL-2 did not show any obvious effect. Human cell markers (CD2 and CD19) were significantly higher in the group of HurIL-4 treated Hu-PBMC than in the other groups, despite the high variability in human cell proliferation in the recipients. Thus, HurIL-4 can be used as an adjuvant growth factor which improves successful engraftment of human peripheral blood lymphocytes in scid mice.     

Cryptosporidium parvum infection of human intestinal xenografts in SCID mice induces production of human tumor necrosis factor alpha and interleukin-8

The protozoan parasite Cryptosporidium parvum invades intestinal epithelial cells and can cause life-threatening diarrhea in immunocompromised individuals. Despite the clinical importance of this organism, much remains to be learned about the pathogenesis of C. parvum-induced diarrhea. To explore the role of the intestinal inflammatory response in C. parvum disease, using C. parvum oocysts we infected human intestinal xenografts in severe combined immunodeficient (SCID) mice. Seven days after infection, we found levels of human tumor necrosis factor alpha and interleukin-8 in C. parvum-infected human intestinal xenografts that were significantly higher than those seen in uninfected control xenografts. These results demonstrate that human intestinal cells produce proinflammatory cytokines in response to C. parvum infection and establish SCID-HU-INT mice as a model system to study the interactions of C. parvum with the human intestine.     

Saturable function of P-glycoprotein as a drug-efflux pump in multidrug-resistant tumour cells

In the past, Mycobacterium avium complex (MAC) was considered a colonizing microbe in the immunocompetent host. Today it should be considered a potential pathogen. We present a case of MAC necrotizing pneumonia in a 27-year-old man who tested negatively for the human immunodeficiency virus, had no typical granulomas, and responded rapidly to antimicrobial therapy.     

Cell therapy of a highly invasive human breast carcinoma implanted in immunodeficient (SCID) mice

Although enormous progress has been made in the detection and treatment of localized (nonmetastatic) breast cancer, there has been relatively moderate progress toward the effective treatment of advanced disease. This study investigates the antitumor efficacy of a potent MHC nonrestricted cytotoxic human T cell line (TALL-104) upon transfer into a clinically relevant mouse model of metastatic breast cancer. Fragments from a surgical specimen of a patient with infiltrating ductal carcinoma were implanted s.c. in the flank region of severe combined immunodeficient (SCID) mice. One hundred % of the animals developed a local tumor mass that metastasized to subaxillary and inguinal lymph nodes, bones, lungs, liver, kidneys, ovaries, and brain, very closely mimicking the human disease. Multiple i.p. transfers of gamma-irradiated (nonproliferating) TALL-104 cells into mice bearing low tumor burden (the primary tumor mass weighed only 150 mg) completely arrested local tumor growth and prevented systemic spread into local lymph nodes and distant organs. Remarkably, cell therapy administered in an advanced disease stage (when the tumor weighed 2 g) induced a significant or total regression of established metastasis with no obvious effects on the primary tumor mass. Profound antitumor effects against both local and systemic disease were instead seen in mice that received cell therapy after surgical excision of the primary tumor. The implications of these data in adjuvant breast cancer therapy are discussed.     

Treatment of human immunodeficiency virus (HIV)-associated nephropathy

Patients with human immunodeficiency virus (HIV) nephropathy (HIVN) face improved outlooks both before and after starting renal replacement therapy for end-stage renal disease, compared with the situation a little over a decade and a half before, when the disease was first recognized. Therapy with cyclosporin, glucocorticoids, and angiotensin-converting enzyme inhibitors provides the prospect of longer courses of renal insufficiency for patients with HIVN, and perhaps the hope of blunting progression of the disease when patients are treated early. Trials of patients with biopsy-proven HIVN are important to evaluate further the role of such newer therapies. HIV-infected patients with end-stage renal disease have been treated with hemodialysis, peritoneal dialysis, and renal transplantation. The course of therapy for dialysis patients may be improving, but ultimately depends on the stage of the viral illness. The disparities in the demographic composition of the patient populations probably underlies findings reported from different centers. Transplantation is currently a low-priority treatment option for HIV-infected patients with ESRD, but several studies provide fascinating insights into viral-host interactions.     

Risk factors and outcome of human immunodeficiency virus-infected patients with sporadic multidrug-resistant tuberculosis in New York City

The discovery of neuroendocrine differentiation in hormone-refractory prostatic adenocarcinoma has opened a potentially new therapeutic approach in this group of patients with a poor prognosis and few effective therapy modalities. Based on previous findings of increased uptake of 11C-5-hydroxytryptophan (11C-5-HTP) in neuroendocrine tumours using the PET technique, this tracer was applied in the study of 10 patients with metastatic hormone-refractory prostatic adenocarcinoma. In three patients, the study was repeated after treatment. An increased uptake of 11C-5-HTP was observed in all investigated skeletal lesions, although the magnitude of the uptake was moderate. The difference between the standard uptake values (SUV) in normal bone and metastatic lesions was significant (p < 0.001). A kinetic analysis of the uptake of 11C-5-HTP demonstrates an increase during the first minutes followed by a wash-out and a stabilization of the tissue/blood ratio at about 2. The Patlak plots demonstrated a gradual increase in the transport rate during the first 20 to 30 min, after which a constant level was observed. The SUV varied between patients and between lesions over time and treatment. The uptake of 11C-5-HTP discriminates metastatic lesions from normal bone and may thus aid in the diagnosis and, potentially, in treatment monitoring of metastatic hormone-refractory prostatic adenocarcinoma. Uptake kinetics are characterized by a wash-out and cannot alone be used as proof of neuroendocrine differentiation in hormone-refractory prostatic adenocarcinoma.     

Severe combined immunodeficiency with cartilage-hair hypoplasa: in vitro response to thymosin and attempted reconstitution

The present report describes an infant with severe combined immunodeficiency and cartilage-hair hypoplasia whose lymphocytes responded to thymosin in vitro. Immunologic evaluation was undertaken at 4 1/2 months of age following a history of recurrent severe infection. Family history included three cousins who died in early infancy, one from streptococcal meningitis and pneumonia, one from generalized varicella, and another from reticuloendotheliosis. Quantitative immunoglobulins were markedly depressed: IgG 141, IgA 0, and IgM 24 mg/100 ml. There was an absolute lymphopenia, multiple skin tests were negative, and in vitro lymphocyte responses to mitogens and antigens were depressed. Spontaneous E rosette determinations were 21% compared with control values of 65.7%. Erythrocyte adenosine deaminase (ADA) activity was normal. The patient's E rosette formation increased in the presence of thymosin, fraction 5, reaching a maximum of 56% with a concentration of 500 mug thymosin. Blastogenic responses to phytohemagglutinin also increased in the presence of thymosin. Transplantation of 24-week fetal thymus in Millipore diffusion chambers and subsequently transplantation of 18-week fetal thymus by intraperitoneal injection was accomplished. E rosettes increased to 35-40% and blastogenic responses to mitogens increased. Eight days after the second transplant the patient underwent a mild graft vs. host reaction which subsided after 1 week and mitogen blastogenic responses again increased to 5-8 times previous values, but still well below control ranges. Repeated episodes of pulmonary infection ensued, cor pulmonale resulted, and the clinical course was relentlessly downhill with the patient expiring from respiratory failure 5 months after transplantation.     

Hybridization of a human myeloma permanent cell line with mouse cells

A population of hybrid cells derived from the fusion of a permanent human myeloma cell line, which secretes complete IgE, and a subline of mouse L cells, did not secrete IgE as evidenced by sensitive immunosorbent tests. Also, the hybrid cells were observed not to contain intracellular IgE (epsilon or lambda chains) in amounts to be detectable by fluorescent antibody techniques. The doubling times and cell cycle parameters of the hybrid cells were found to be similar to those of the slow-growing parental human myeloma cells, in addition, the growth of the hybrid cells was characterized by a higher degree of contact inhibition than the parent mouse cells.     

The efficacy of 2',2'-difluorodeoxycytidine (gemcitabine) and vinblastine combined with interferon in nude mice xenografts of human renal cell carcinoma

Recent in vitro experiments indicated strong activity of 2',2'-difluorodeoxycytidine (dFdC, gemcitabine) in human renal cell carcinoma (RCC) cell lines and an increase of efficacy by combined application of interferon (IFN). In the present study, nude mice with xenografts from ACHN- or SN12C cells were treated by dFdC, dFdC plus IFN-alpha or vinblastine (VBL) plus IFN-alpha. ACHN-xenografts were significantly more inhibited by dFdC+/-IFN-alpha than by VBL+IFN-alpha. Complete remissions (CR) were only seen by dFdC. An additional treatment with IFN-alpha shortened the time to commencement of tumor remission and increased CR of ACHN- and SN12C-tumors (40%; 7%) compared to a treatment with dFdC alone (20%; 0). dFdC+IFN-alpha reduced the number of pulmonary metastases compared to untreated animals. Survival was significantly prolonged by dFdC+/-IFN-alpha in ACHN-mice and dFdC+IFN-alpha or VBL+IFN-alpha in SN12C mice. In conclusion, experimental data confirm dFdC as a superior drug against human RCC compared to VBL. Combined therapy with IFN-alpha increased the efficacy of dFdC in terms of tumor response in immunodeficient nude mice, thus clinical studies are strongly recommended in patients with metastatic renal cell carcinoma.